When ground faults occur on new energy-integrated lines
the weak fault current injection and strong controllability of new energy sources can degrade distance protection performance. To address the insufficient sensitivity of conventional power-frequency distance protection during ground faults with transition resistance on new energy-integrated lines and the low reliability of conventional time-domain distance protection
this paper proposes a time-domain distance protection method based on impedance compensation for single-phase-to-ground faults. First
the equivalent transition resistance at the fault point is solved in real time by establishing time-domain equations. Then
the relationship between the additional impedance and the equivalent transition resistance is established to derive an accurate impedance compensation model
forming the impedance-compensated time-domain distance protection criterion. Finally
PSCAD/EMTDC simulations verify that the proposed scheme significantly enhances the sensitivity of distance protection during transition resistance faults while ensuring reliability
demonstrating practical applicability for new energy integration via AC lines.